There is considerable interest in finding ways to convert biomass into valuable products, especially products that can be used as transportation fuels or in other chemical processes.
US Patent Application Publication No. 2010/0251600, which is herein incorporated by reference, describes a multi-stage process for producing liquid products from biomass in which the biomass is hydropyrolyzed in a reactor vessel containing molecular hydrogen and a deoxygenating catalyst, producing a partially deoxygenated pyrolysis liquid, char, and first stage process heat. The partially deoxygenated pyrolysis liquid is hydrogenated using a hydroconversion catalyst, producing a substantially fully deoxygenated pyrolysis liquid, a gaseous mixture comprising carbon monoxide and light hydrocarbon gases (C1-C4), and second stage process heat. The gaseous mixture is then reformed in a steam reformer, producing reformed molecular hydrogen. The reformed molecular hydrogen is then introduced into the reactor vessel for the hydropyrolysis of additional biomass.
Continued improvements in this type of process are needed so that it will be economically and technically feasible and able to be carried out on a commercial scale.